Description

Implementation of XCDR introduces new functions in TopicDataType class. But the old one remained. This PR removes them before launching the major version 3, and also performs additional refactorings:

• Change method names to snake_case and have more meaningful names.
• Change arguments from pointer to reference where applicable
• Use std::string instead of char* on name getters and setters

Depends on:

• [21351] Refactor TopicDataType Fast-DDS-Gen#375
• [21373] Update to new TopicDataType functions Fast-DDS-python#165
• [21374] Refactor TopicDataType ShapesDemo#166
• [21376] Refactor TopicDataType Discovery-Server#97
• [21378] Refactor TopicDataType Fast-DDS-docs#875

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• N/A Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• Any new/modified methods have been properly documented using Doxygen.
• N/A Any new configuration API has an equivalent XML API (with the corresponding XSD extension)
• ❌ Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• ❌ Changes are API compatible.
• N/A New feature has been added to the versions.md file (if applicable).
• N/A New feature has been documented/Current behavior is correctly described in the documentation.
• N/A Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• N/A If this is a critical bug fix, backports to the critical-only supported branches have been requested.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.